Illumination unit and display apparatus using the same

ABSTRACT

An illumination unit, can include first and second reflectors, and at least one light source module disposed between the first and second reflectors, wherein the second reflector includes at least one inclined surface including at least one inflection point, and at least one first flat surface disposed close to the at least one light source module and being parallel to the first reflector.

CROSS REFERENCE TO RELATED APPLICATION

This application is a continuation of co-pending U.S. patent applicationSer. No. 13/711,222 filed on Dec. 11, 2012, which claims priority under35 U.S.C. §119 to Korean Patent Application No. 10-2011-0132885, filedin Korea on 12 Dec. 2011, which are hereby incorporated in theirentirety by reference as if fully set forth herein.

BACKGROUND OF THE INVENTION

1. Technical Field

Embodiments relate to an illumination unit and a display apparatus usingthe same.

2. Background Art

In general, downlights are constructed such that a light source isembedded in a ceiling hole. Such downlights have been widely used asarchitectural illumination means that integrate illumination with abuilding.

The downlight is embedded in the ceiling so as to be substantiallyprevented from being exposed outward, thus advantageously providing anorderly external appearance to the ceiling. Moreover, the downlightembedded in the ceiling may have low luminance and be suitable to forman intimate indoor space.

However, such an illumination unit configuration may be suitable for anarrow indoor space than a wide indoor space, and may need a greatnumber of light sources such as Light Emitting Diodes (LEDs).

Accordingly, in the future, development of an illumination unit suitablefor a wide indoor space even with a low number of LEDs is necessary.

SUMMARY OF THE INVENTION

Embodiments provide an illumination unit which includes a reflectorpartially provided with an inclined surface and is suitable for a wideindoor space, and a display apparatus using the same.

In one embodiment, an illumination unit includes first and secondreflectors, and at least one light source module placed between thefirst and second reflectors, wherein the second reflector includes abottom plate, first lateral plates arranged to face each other in afirst direction of the bottom plate, second lateral plates arranged toface each other in a second direction orthogonal to the first direction,a groove formed in at least one of the second lateral plate and thebottom plate, and at least one hole formed in the groove.

The light source module may be placed on the first lateral plate of thesecond reflector, and may include at least one connector for electricconnection with an external component.

In this case, the groove may be located close to the connector.

The illumination unit may further include at least one drive unit placedbelow the bottom plate of the second reflector and serving to drive thelight source module, and at least one line placed through the groove andthe hole to electrically connect the light source module and the driveunit to each other.

The groove may have a width and a depth which differ from each other,and the width of the groove may be less than the depth of the groove.

The width of the groove may differ from the width of the hole, and thewidth of the groove may be greater than the width of the hole.

The width of the groove may be equal to the width of the hole.

The groove may include first and second lateral surfaces facing eachother, and a bottom surface located between the first and second lateralsurfaces, and a first angle between the first lateral surface and thebottom surface and a second angle between the second lateral surface andthe bottom surface may be an acute angle.

Here, the first angle and the second angle may differ from each other.The first angle may be a right angle and the second angle may be anacute angle. Alternatively, the first angle may be an acute angle andthe second angle may be a right angle.

The first lateral surface may be a curved surface having a first radiusof curvature, the second lateral surface may be a curved surface havinga second radius of curvature, and the first radius of curvature and thesecond radius of curvature may differ from each other.

The bottom plate of the second reflector may include at least oneinclined surface.

The at least one inclined surface may include at least one inflectionpoint such that inclined surfaces, which are located next to each otherabout the inflection point, have different radii of curvature.

The light source module may be spaced apart from the first reflector bya first distance, and may be spaced apart from the second reflector by asecond distance. The first distance and the second distance may differfrom each other.

The light source module may come into contact with at least one of thefirst and second reflectors.

A thickness of a region of the first reflector close to the light sourcemodule may differ from a thickness of a region of the first reflectordistant from the light source module, and the first reflector mayinclude a reflective pattern formed on a surface thereof facing thelight source module.

The first reflector and the second reflector may be formed of differentmaterials.

In another embodiment, an illumination unit includes a bottom plate,first lateral plates arranged to face each other in a first direction ofthe bottom plate, second lateral plates arranged to face each other in asecond direction orthogonal to the first direction, a groove formed inat least one of the second lateral plate and the bottom plate, and atleast one hole formed in the groove, wherein the light source moduleincluding a connector is placed on the first lateral plate, and aportion of the connector overlaps with the groove of the second lateralplate.

BRIEF DESCRIPTION OF THE DRAWINGS

Arrangements and embodiments may be described in detail with referenceto the following drawings in which like reference numerals refer to likeelements and wherein:

FIG. 1 is an explanatory perspective view illustrating an illuminationunit according to an embodiment;

FIG. 2 is a view illustrating a position of a groove according to afirst embodiment;

FIGS. 3A and 3B are views illustrating electric connection between alight source module and a drive unit according to the first embodiment;

FIG. 4 is a sectional view taken along the line I-I of FIG. 3A;

FIGS. 5A and 5B are sectional views taken along the line II-II of FIG.3A;

FIGS. 6A to 6D are sectional views illustrating different shapes of thegroove;

FIGS. 7 and 8 are views illustrating a position of the groove accordingto a second embodiment;

FIGS. 9 and 10 are views illustrating positions of recesses according toa third embodiment;

FIG. 11 is a view illustrating an inclined surface of a second reflectoraccording to a first embodiment;

FIGS. 12A to 12C are explanatory views illustrating an arrangementrelationship between a light source module and first and secondreflectors;

FIGS. 13A and 13B are views comparing a width of a first region of thesecond reflector with a width of the first reflector;

FIGS. 14A to 14D are views illustrating different inclined surfaces forthe second reflector;

FIG. 15 is a view illustrating an inclined surface of a second reflectoraccording to a second embodiment;

FIGS. 16A to 16C are views illustrating a fourth region of FIG. 15;

FIGS. 17A to 17D are views illustrating a first reflector having aninclined surface;

FIGS. 18A to 18D are views illustrating a first reflector having areflective pattern;

FIG. 19 is a sectional view illustrating an illumination unit includingan optical member;

FIG. 20 is a sectional view illustrating the optical member of FIG. 19;

FIG. 21 is a view illustrating a display module having an illuminationunit according to an embodiment; and

FIGS. 22 and 23 are views illustrating a display apparatus according toan embodiment.

DETAILED DESCRIPTION OF THE INVENTION

Hereinafter, embodiments will be described with reference to the annexeddrawings.

It will be understood that when an element is referred to as being ‘on’or “under” another element, it can be directly on/under the element, andone or more intervening elements may also be present.

Also, when an element is referred to as being ‘on’ or ‘under’, ‘underthe element’ as well as ‘on the element’ can be included based on theelement.

FIG. 1 is an explanatory perspective view illustrating an illuminationunit according to an embodiment.

As illustrated in FIG. 1, the illumination unit may include first andsecond reflectors 200 and 300, and at least one light source module 100placed between the first and second reflectors 200 and 300.

The light source module 100 may be located between the first reflector200 and the second reflector 300 and may be located closer to the firstreflector 200 than the second reflector 300.

As occasion demands, the light source module 100 may come into contactwith the first reflector 200 while being spaced apart from the secondreflector 300 by a predetermined distance, or may come into contact withthe second reflector 300 while being spaced apart from the firstreflector 200 by a predetermined distance.

Alternatively, the light source module 100 may be spaced apart from thefirst reflector 200 and the second reflector 300 by predetermineddistances, or may come into contact with both the first reflector 200and the second reflector 300.

The light source module 100 may include a board 100 b having anelectrode pattern, at least one light source 100 a placed on the board100 b, and at least one connector 100 c for electric connection with anexternal component.

The light source 100 a of the light source module 100 may be a top viewtype light emitting diode.

As occasion demands, the light source 100 a may be a side view typelight emitting diode.

The board 100 b may be a Printed Circuit Board (PCB) formed of any onematerial selected from among polyethyleneterephthalate (PET), glass,polycarbondate (PC), and silicon (Si), and may take the form of a film.

A single layer PCB, a multilayer PCB, a ceramic board, a metal core PCB,or the like may be selectively used as the board 100 b.

The board 100 b may be provided with any one of a reflective coatingfilm and a reflective coating material layer, to reflect light emittedfrom the light source 100 a to a central region of the reflector 300.

The light source 100 a may be a Light Emitting Diode (LED) chip. The LEDchip may be a blue LED chip or an ultraviolet LED chip, or may be apackage combining at least one or more selected from among a red LEDchip, a green LED chip, a blue LED chip, a yellow green LED chip, and awhite LED chip.

A white LED may be realized by coupling a yellow phosphor to a blue LED,by coupling both red and green phosphors to a blue LED, or by couplingyellow, red and green phosphors to a blue LED.

The first reflector 200 and the second reflector 300 may be spaced apartfrom each other by a predetermined distance so as to face each other,such that an air guide is defined in an empty space between the firstreflector 200 and the second reflector 300.

The first reflector 200 may have an open region, and may come intocontact with one side of the light source module 100 or may be spacedapart from the light source module 100 by a predetermined distance.

More specifically, the first reflector 200 may have an open centralregion, and the light source module 100 may include a first light sourcemodule and a second light source module which are arranged at oppositeedge regions of the first reflector 200 so as to face each other.

The first reflector 200 may be formed of any one of a reflective coatingfilm and a reflective coating material layer and may serve to reflectlight emitted from the light source module 100 toward the secondreflector 300.

A saw-toothed reflective pattern may be formed on a surface of the firstreflector 200 facing the light source module 100. The reflective patternmay be flat or may be curved.

The reason for providing the surface of the first reflector 200 with thereflective pattern is to reflect light emitted from the light sourcemodule 100 toward the central region of the second reflector 300,thereby increasing luminance of the central region of the illuminationunit.

The second reflector 300 may include a bottom plate 310 and lateralplates 320.

The lateral plates 320 may include a pair of first lateral plates 320 a,which are arranged to face each other in a first direction (Y-directionof FIG. 2) of the bottom plate 310, and a pair of second lateral plates320 b which are arranged to face each other in a second direction(X-direction of FIG. 2) orthogonal to the first direction.

The light source module 100 and the first reflector 200 may be placedover the first lateral plate 320 a.

The second lateral plate 320 b may have a groove.

More specifically, the groove 110 may be formed in an upper surface 320b 2 of the second lateral plate 320 b and serve as a passage of a linethat electrically connects the connector 100 c of the light sourcemodule 100 and a drive unit to each other.

Here, at least one hole may be perforated in the groove 110.

As such, the drive unit to drive the light source module 100 may belocated below the bottom plate 310 of the second reflector 300, and atleast one line may pass through the groove 110 and the hole so as toelectrically connect the light source module 100 and the drive unit toeach other.

Through the aforementioned line connection, the groove 110 may belocated close to the connector 100 c of the light source module 100.

The second lateral plate 320 b may have more than one first couplingportion 322 for coupling with an optical member and more than one secondcoupling portion 334 for coupling with a cover member.

The first coupling portion 322 may be formed on the upper surface 320 b2 of the second lateral plate 320 b, and the second coupling portion 334may be formed on an outer surface 320 b 3 of the second lateral plate320 b.

In this case, the first coupling portion 322 and the second couplingportion 334 may be provided to correspond to each other in a one to oneratio.

The first coupling portion 322 may protrude upward (in Z-direction ofFIG. 2) from the upper surface 320 b 2 of the second lateral plate 320b. The second coupling portion 334 may protrude in the second direction(X-direction of FIG. 2) from the outer surface 320 b 3 of the secondlateral plate 320 b.

A reflective coating film or a deposited reflective coating materiallayer may be formed over an inner surface 320 b 1 of the second lateralplate 320 b and the bottom plate 310.

Although the same reflective material may be formed over the innersurface 320 b 1 of the second lateral plate 320 b and the bottom plate310, different materials may be formed as occasion demands.

The bottom plate 310 of the second reflector 300 may be spaced apartfrom the light source module 100 by a predetermined distance and mayhave an inclined surface having a predetermined inclination angle withrespect to a horizontal plane that is parallel to the surface of thefirst reflector 200.

The inclined surface of the bottom plate 310 of the second reflector 300may serve to reflect the light, emitted from the light source module 100or reflected from the first reflector 200, toward the open region of thefirst reflector 200.

The bottom plate 310 of the second reflector 300 may include at leasttwo inclined surfaces having at least one inflection point.

In the bottom plate 310 of the second reflector 300, the first andsecond inclined surfaces, which are located next to each other about theinflection point, may have different radii of curvature.

The inflection point between the first and second inclined surfaces maybe located close to the light source module 100.

This is because the radius of curvature of the first inclined surfaceclose to the light source module 100 is greater than the radius ofcurvature of the second inclined surface.

A reflective coating film or a deposited reflective coating materiallayer may be formed over an upper surface of the bottom plate 310 of thesecond reflector 300.

Accordingly, the bottom plate 310 of the second reflector 300 mayinclude at least one of a metal or metal oxide. For example, the bottomplate 310 may be formed of a metal or metal oxide having highreflectivity, such as aluminum (Al), silver (Ag), gold (Au) or titaniumdioxide (TiO2).

In this case, the bottom plate 310 of the second reflector 300 may beformed by depositing or coating a metal or metal oxide on the uppersurface thereof, or may be formed by printing metallic ink.

Here, deposition may be performed by thermal deposition, evaporation, orvacuum deposition such as sputtering, and coating or printing may beperformed by gravure coating, silk screen printing, or the like.

As occasion demands, the second reflector 300 may be provided with atleast one of a specular-reflection sheet and a diffuse-reflection sheet.

In the bottom plate 310 of the second reflector 300, the first andsecond inclined surfaces may be formed of the same material or differentmaterials and may have different surface roughness values.

More specifically, in the bottom plate 310 of the second reflector 300,the first and second inclined surfaces may be formed of the samematerial, but may have different surface roughness values.

Alternatively, in the bottom plate 310 of the second reflector 300, thefirst and second inclined surfaces may be formed of different materialsand may have different surface roughness values.

FIG. 2 is a view illustrating a position of the groove according to afirst embodiment.

As illustrated in FIG. 2, the second reflector 300 may include thebottom plate 310 and the lateral plates 320.

The lateral plates 320 may include the first lateral plates 320 a, whichare arranged to face each other in the first direction (Y-direction ofFIG. 2) of the bottom plate 310, and the second lateral plates 320 bwhich are arranged to face each other in the second direction(X-direction of FIG. 2) orthogonal to the first direction.

The light source module 100 and the first reflector 200 may be placedover the first lateral plate 320 a.

The light source module 100 may include the board 100 b having anelectrode pattern, the at least one light source 100 a placed on theboard 100 b, and the at least one connector 100 c for electricconnection with an external component.

The second lateral plate 320 b may include the groove 110.

More specifically, the groove 110 may be formed in the upper surface 320b 2 of the second lateral plate 320 b and serve as a passage of a linethat electrically connects the connector 100 c of the light sourcemodule 100 and the drive unit to each other.

The at least one hole 112 may be perforated in the groove 110.

As such, if the drive unit to drive the light source module 100 islocated below the bottom plate 310 of the second reflector 300, a lineelectrically connected to the connector 100 c of the light source module100 may pass through the groove 110 and the hole 112 to thereby beelectrically connected to the drive unit below the bottom plate 310.

The light source module 100 including the connector 100 c may be placedon the first lateral plate 320 a such that a portion of the connector100 c overlaps with the groove 110 of the second lateral plate 320 b.

FIGS. 3A and 3B are views illustrating electric connection between thelight source module and the drive unit according to the firstembodiment. FIG. 3A illustrates the groove viewed from the top, and FIG.3B illustrates the groove viewed from the bottom.

As illustrated in FIG. 3A, the light source module 100 may include theboard 100 b having the electrode pattern, the at least one light source100 a placed on the board 100 b, and the at least one connector 100 cfor electric connection with an external component.

The groove 110 may be formed in the upper surface 320 b 2 of the secondlateral plate 320 b and serve as a passage of a line 114 thatelectrically connects the connector 100 c of the light source module 100and the drive unit to each other.

The at least one hole 112 may be perforated in the groove 110.

As illustrated in FIG. 3B, the drive unit 370 to drive the light sourcemodule 100 may be located below the bottom plate 310 of the secondreflector 300, and the at least one line 114 may pass through the groove110 and the hole 112 so as to electrically connect the light sourcemodule 100 and the drive unit 370 to each other.

As such, the groove 110 may be located close to the connector 100 c ofthe light source module 100.

FIG. 4 is a sectional view taken along the line I-I of FIG. 3A.

As illustrated in FIG. 4, the groove 110 may be formed in the uppersurface 320 b 2 of the second lateral plate 320 b and serve as a passageof the line 114 that electrically connects the connector 100 c of thelight source module 100 and the drive unit 370 to each other. The groove110 may be defined by a bottom surface 110 a and a lateral surface 110b.

The lateral surface 110 b of the groove 110 may be a flat surfaceorthogonal to the bottom surface 110 a.

As occasion demands, the lateral surface 110 b of the groove 110 may beinclined with respect to the bottom surface 110 a.

The groove 110 may have a width w and a depth d which differ from eachother.

For example, the width w of the groove 110 may be less than the depth dof the groove 110.

As occasion demands, the groove may have a width w and a depth d thatare equal to each other.

Although the single line 114 may be placed in the groove 110, aplurality of lines 114 may be stacked one above another in the groove110.

Accordingly, the depth d of the groove 110 may be determined based onthe number of the lines 114.

FIGS. 5A and 5B are sectional views taken along the line II-II of FIG.3A.

As illustrated in FIGS. 5A and 5B, the second lateral plate 320 b mayhave the groove 110 and the hole 112, which serve as a passage of theline that electrically connects the connector of the light source moduleand the drive unit to each other.

As illustrated in FIG. 5A, a width w1 of the groove 110 may differ froma width w2 of the hole 112.

For example, the width w1 of the groove 110 may be greater than thewidth w2 of the hole 112.

This is because a plurality of lines may be placed in the groove 110,but only some of the lines may pass through the hole 112.

Accordingly, the configuration of FIG. 5A is applicable to embodimentsin which some of the plurality of lines placed in the groove 110 passthrough the hole 112.

As occasion demands, as illustrated in FIG. 5B, the width w1 of thegroove 110 may be equal to the width w2 of the hole 112.

As such, the width w1 of the groove 110 and the width w2 of the hole 112may be determined based on various arrangements of the lines.

In another embodiment, a plurality of different holes 112 may be formedin the single groove 110.

FIGS. 6A to 6D are sectional views illustrating different shapes of thegroove.

As illustrated in FIGS. 6A to 6D, the second lateral plate 320 b has thegroove 110 that serves as a passage of a line that electrically connectsthe connector 100 c of the light source module and the drive unit toeach other. The groove 110 may include first and second lateral surfaces110 b 1 and 110 b 2 facing each other, and the bottom surface 110 alocated between the first and second lateral surfaces 110 b 1 and 110 b2.

As illustrated in FIG. 6A, a first angle θ1 between the first lateralsurface 110 b 1 and the bottom surface 110 a and a second angle θ2between the second lateral surface 110 b 2 and the bottom surface 110 amay be an acute angle.

In this case, the first angle θ1 and the second angle θ2 may differ fromeach other, but may be equal to each other as occasion demands.

The first angle θ1 may be a right angle and the second angle θ2 may bean acute angle as illustrated in FIG. 6B, or the first angle θ1 may bean acute angle and the second angle θ2 may be a right angle asillustrated in FIG. 6C.

As occasion demands, as illustrated in FIG. 6D, the first lateralsurface 110 b 1 may be a curved surface having a first radius ofcurvature R1, and the second lateral surface 110 b 2 may be a curvedsurface having a second radius of curvature R2.

The first radius of curvature R1 and the second radius of curvature R2may differ from each other, but may be equal to each other, as occasiondemands.

The reason for providing the groove 110 with a wider bottom end and anarrower top end is to prevent the line(s) placed in the groove 110 frombeing visible from the outside, thereby enabling fabrication of anillumination unit having a pleasant outer appearance and preventingdamage to the line(s) due to external shock.

FIGS. 7 and 8 are views illustrating a position of the groove accordingto a second embodiment. FIG. 7 is a plan view illustrating the top ofthe groove, and FIG. 8 is a view illustrating the bottom of the groove.

Although FIG. 2 illustrates one embodiment of a position of the groove110 in a configuration in which the connector 100 c of the light sourcemodule 100 is located at one side of the board 100 b, FIGS. 7 and 8illustrate another embodiment of a position of the groove 110 in aconfiguration in which a pair of connectors 100 c of the light sourcemodule 100 is arranged respectively at both sides of the board 100 b.

As illustrated in FIGS. 7 and 8, the second reflector 300 may includethe bottom plate 310 and the lateral plates 320.

The lateral plates 320 may include the first lateral plates 320 a, whichare arranged to face each other in the first direction (Y-direction ofFIG. 2) of the bottom plate 310, and the second lateral plates 320 bwhich are arranged to face each other in the second direction(X-direction of FIG. 2) orthogonal to the first direction.

The light source module 100 may be placed on the first lateral plate 320a.

The light source module 100 may include the board 100 b having theelectrode pattern, the at least one light source 100 a placed on theboard 100 b, and the at least one connector 100 c for electricconnection with an external component.

In this case, the connectors 100 c of the light source module 100 may belocated respectively at both sides of the board 100 b.

The second lateral plate 320 b may have the groove 110 formed in theupper surface 320 b 2 thereof, and the groove 110 serves as a passage ofa line that electrically connects a corresponding one of the connectors100 c of the light source module 100 and the drive unit to each other.

The at least one hole 112 may be perforated in the groove 110.

As illustrated in FIG. 8, the drive unit 370 to drive the light sourcemodule 100 may be located below the bottom plate 310 of the secondreflector 300, and the at least one line 114 may pass through the groove110 and the hole 112 so as to electrically connect the light sourcemodule 100 and the drive unit 370 to each other.

As such, the groove 110 may be located close to the correspondingconnector 100 c of the light source module 100.

In the aforementioned configuration in which the connectors 100 c of thelight source module 100 are located at both sides of the board 100 b,the groove 110 may be formed in each of the second lateral plates 320 barranged to face each other.

FIGS. 9 and 10 are views illustrating a position of the groove accordingto a third embodiment. FIG. 9 is a plan view illustrating the top of thegroove, and FIG. 10 is a view illustrating the bottom of the groove.

FIG. 2 illustrates one embodiment of a position of the groove 110 in aconfiguration in which the connector 100 c of the light source module100 is located at one side of the board 100 b, FIGS. 7 and 8 illustrateanother embodiment of a position of the groove 110 in a configuration inwhich a pair of connectors 100 c of the light source module 100 isarranged respectively at both sides of the board 100 b, and FIGS. 9 and10 illustrate the other embodiment of a position of the groove 110 in aconfiguration in which the connector 100 c of the light source module100 is located at the center of the board 100 b.

As illustrated in FIGS. 9 and 10, the second reflector 300 may includethe bottom plate 310 and the lateral plates 320.

The lateral plates 320 may include the first lateral plates 320 a, whichare arranged to face each other in the first direction (Y-direction ofFIG. 2) of the bottom plate 310, and the second lateral plates 320 bwhich are arranged to face each other in the second direction(X-direction of FIG. 2) orthogonal to the first direction.

The light source module 100 may be placed on the first lateral plate 320a.

The light source module 100 may include the board 100 b having theelectrode pattern, the at least one light source 100 a placed on theboard 100 b, and the at least one connector 100 c for electricconnection with an external component.

In this case, the connector 100 c of the light source module 100 may belocated at the center of the board 100 b.

The bottom plate 310 located close to the connector 100 c of the lightsource module 100 may have the groove 110 that serves as a passage of aline that electrically connects the connector 100 c of the light sourcemodule 100 and the drive unit to each other.

The at least one hole 112 may be perforated in the groove 110.

As illustrated in FIG. 10, the drive unit 370 to drive the light sourcemodule 100 may be located below the bottom plate 310 of the secondreflector 300, and the at least one line 114 may pass through the groove110 and the hole 112 so as to electrically connect the light sourcemodule 100 and the drive unit 370 to each other.

As such, the groove 110 may be located close to the connector 100 c ofthe light source module 100.

In the aforementioned configuration in which the connector 100 c of thelight source module 100 is located at the center of the board 100 b, thegroove 110 may be formed in the bottom plate 310.

FIG. 11 is a view illustrating an inclined surface of the secondreflector according to a first embodiment.

As illustrated in FIG. 11, the light source module 100 is locatedbetween the first and second reflectors 200 and 300. The secondreflector 300 may include at least one inclined surface and at least oneflat surface. The flat surface of the second reflector 300 may belocated close to the light source module 100 and may be parallel to thefirst reflector 200.

The inclined surface of the second reflector 300 may include at leastone inflection point. That is, inclined surfaces, which are located nextto each other about the inflection point, may have different radii ofcurvature.

For example, the second reflector 300 may include first, second, andthird regions.

The first region may be aligned with the light source module 100 and thefirst reflector 200, and may be a flat surface parallel to the firstreflector 200.

The second region, which is located between the first region and thethird region, may be a first inclined surface that is inclined downwardfrom the first region. The third region, which is located next to thesecond region, may be a second inclined surface that is inclined upwardfrom the second region.

The first inclined surface of the second region and the second inclinedsurface of the third region may be located next to each other about aninflection point P.

In this case, the first inclined surface of the second region may be acurved surface having a first radius of curvature R1, and the secondinclined surface of the third region may be a curved surface having asecond radius of curvature R2.

The first radius of curvature R1 and the second radius of curvature R2may differ from each other, and the first radius of curvature R1 may begreater than the second radius of curvature R2.

As occasion demands, the first radius of curvature R1 and the secondradius of curvature R2 may be equal to each other.

At least one of the first inclined surface of the second region and thesecond inclined surface of the third region may be a convexly curvedsurface or a concavely curved surface.

As occasion demands, the first inclined surface of the second region maybe a flat surface having a first gradient and the second inclinedsurface of the third region may be a flat surface having a secondgradient.

In this case, the first gradient and the second gradient may differ fromeach other, and the first gradient may be greater than the secondgradient.

The first region of the second reflector 300 may be provided with aspecular-reflection sheet. The second region and the third region of thesecond reflector 300 may be provided with at least one of aspecular-reflection sheet and a diffuse-reflection sheet.

The specular-reflection sheet formed on the first region of the secondreflector 300 serves to reflect light to a low luminance central regionof the second reflector 300, which achieves uniform luminance.

Additionally, since the first region of the second reflector 300 is theflat surface parallel to the first reflector 200, concentrating agreater quantity of light emitted from the light source module 100 onthe low-luminance central region of the second reflector 300 mayincrease luminance at a central region of the illumination unit.

The second reflector 300 may be formed of a metal or metal oxide havinghigh reflectivity, such as aluminum (Al), silver (Ag), gold (Au) ortitanium dioxide (TiO2). The first, second and third regions of thesecond reflector 300 may be formed of the same material or differentmaterials, and may have different surface roughness values.

More specifically, the first, second and third regions of the secondreflector 300 may be formed of the same material, but may have differentsurface roughness values.

Alternatively, the first, second and third regions of the secondreflector 300 may be formed of different materials and may havedifferent surface roughness values.

FIGS. 12A to 12C are explanatory views illustrating an arrangementrelationship between the light source module and the first and secondreflectors.

FIG. 12A illustrates the light source module 100 spaced apart from thefirst reflector 200 and the second reflector 300 by predetermineddistances. FIG. 12B illustrates the light source module 100 coming intocontact with the first reflector 200 while being spaced apart from thesecond reflector 300 by a predetermined distance. FIG. 12C illustratesthe light source module 100 coming into contact with both the firstreflector 200 and the second reflector 300.

As illustrated in FIG. 12A, the light source module 100 may be spacedapart from the first reflector 200 by a first distance d1 and may bespaced apart from the second reflector 300 by a second distance d2.

Here, the first distance d1 and the second distance d2 may be equal toeach other, or may differ from each other.

For example, the first distance d1 may be less than the second distanced2.

This is because a hot spot phenomenon may occur if the first distance d1is greater than the second distance d2.

As illustrated in FIG. 12B, the light source module 100 may come intocontact with the first reflector 200 and may be spaced apart from thesecond reflector 300 by a distance d.

When the light source module 100 comes into contact with the firstreflector 200, it is possible to prevent a hot spot phenomenon and totransmit light more distantly from the light source module 100.

As illustrated in FIG. 12C, the light source module 100 may come intocontact with both the first reflector 200 and the second reflector 300.

When the light source module 100 comes into contact with both the firstreflector 200 and the second reflector 300, it is possible to prevent ahot spot phenomenon, to transmit light more distantly from the lightsource module 100, and to reduce a thickness of the entire illuminationunit.

FIGS. 13A and 13B are views comparing a width of the first region of thesecond reflector with a width of the first reflector.

As illustrated in FIG. 13A, the first region of the second reflector 300may overlap with the first reflector 200, and a width W2 of the firstregion of the second reflector 300 may be less than a width W1 of thefirst reflector 200.

Through this configuration, as light reflected from the first region ofthe second reflector 300 is repeatedly reflected from the firstreflector 200, the light may be concentrated on the low luminancecentral region of the second reflector 300.

As illustrated in FIG. 13B, the first region of the second reflector 300may completely overlap with the first reflector 200, and a width of thefirst region of the second reflector 300 may be equal to a width W1 ofthe first reflector 200.

FIGS. 14A to 14D are views illustrating different inclined surfaces forthe second reflector.

As illustrated in FIG. 14A, the second reflector 300 may include thefirst, second and third regions. The first region may be aligned withthe light source module 100 and the first reflector 200 and may be aflat surface parallel to the first reflector 200.

The second region, which is located between the first region and thethird region, may be a first inclined surface that is inclined downwardfrom the first region. The third region, which is located next to thesecond region, may be a second inclined surface that is inclined upwardfrom the second region.

The first inclined surface may be a curved surface having a first radiusof curvature, and the second inclined surface may be a curved surfacehaving a second radius of curvature. The first radius of curvature andthe second radius of curvature may differ from each other.

As occasion demands, at least one of the first and second inclinedsurfaces may be a convexly curved surface or a concavely curved surface.

As illustrated in FIG. 14B, the second reflector 300 may include thefirst, second and third regions. The first region may be aligned withthe light source module 100 and the first reflector 200 and may be aflat surface parallel to the first reflector 200.

The second region, which is located between the first region and thethird region, may be a first inclined surface that is inclined downwardfrom the first region. The third region, which is located next to thesecond region, may be a second inclined surface that is inclined upwardfrom the second region.

The first inclined surface may be a flat surface having a firstgradient, and the second inclined surface may be a flat surface having asecond gradient. The first gradient and the second gradient may differfrom each other.

As illustrated in FIG. 14C, the second reflector 300 may include thefirst, second and third regions. The first region may be aligned withthe light source module 100 and the first reflector 200 and may be aflat surface parallel to the first reflector 200.

The second region, which is located between the first region and thethird region, may be a first inclined surface that is inclined downwardfrom the first region. The third region, which is located next to thesecond region, may be a second inclined surface that is inclined upwardfrom the second region.

The first inclined surface may be a curved surface having apredetermined radius of curvature, and the second inclined surface maybe a flat surface having a predetermined gradient.

As illustrated in FIG. 14D, the second reflector 300 may include thefirst, second and third regions. The first region may be aligned withthe light source module 100 and the first reflector 200 and may be aflat surface parallel to the first reflector 200.

The second region, which is located between the first region and thethird region, may be a first inclined surface that is inclined downwardfrom the first region. The third region, which is located next to thesecond region, may be a second inclined surface that is inclined upwardfrom the second region.

The first inclined surface may be a flat surface having a predeterminedgradient, and the second inclined surface may be a curved surface havinga predetermined radius of curvature.

FIG. 15 is a view illustrating an inclined surface of the secondreflector according to a second embodiment.

Although FIG. 15 illustrates a configuration similar to that of FIG. 11,there is a difference in that a fourth region may be formed next to thethird region of the second reflector 300.

As illustrated in FIG. 15, the second reflector 300 may include a centerfourth region next to the third region.

The fourth region may be a flat surface parallel to the first reflector200, or may be a curved surface having a third radius of curvature.

The fourth region is located at the center of the second reflector 300.The fourth region may have a gentle shape to provide uniform luminancebecause a sharp shape of the fourth region causes a hot spot phenomenondue to light concentration.

FIGS. 16A to 16C are views illustrating the fourth region of FIG. 15.

As illustrated in FIG. 16A, the fourth region of the second reflector300 may be a flat surface parallel to the first reflector.

As illustrated in FIG. 16B, the fourth region of the second reflector300 may be a concavely curved surface having a third radius of curvatureR3. As illustrated in FIG. 16C, the fourth region of the secondreflector 300 may be a convexly curved surface having a third radius ofcurvature R3.

As such, fabricating the fourth region with a gentle shape without apointed portion may reduce a hot spot phenomenon and achieve uniformluminance.

The light source module 100 and the first and second reflectors 200 and300 arranged as described above may be supported by a cover frame.

FIGS. 17A to 17D are views illustrating the first reflector having aninclined surface. FIG. 17A illustrates a flat inclined surface, andFIGS. 17B, 17C and 17D illustrate a curved inclined surface.

As illustrated in FIGS. 17A to 17D, one surface of the first reflector200 facing the second reflector 300 may be inclined with respect to theother surface of the first reflector 200 by a predetermined angle.

Here, the angle θ of the inclined surface may be in a range of 1˜85degrees with respect to a horizontal plane parallel to the other surfaceof the first reflector 200.

A thickness of the first reflector 200 may gradually decrease orincrease with increasing distance from the light source module 100.

More specifically, a thickness t1 of a region of the first reflector 200close to the light source module 100 may differ from a thickness t2 of aregion of the first reflector 200 distant from the light source module100. As illustrated in FIGS. 17A and 17B, the thickness t1 of the regionof the first reflector 200 close to the light source module 100 may begreater than the thickness t2 of the region of the first reflector 200distant from the light source module 100.

As occasion demands, as illustrated in FIGS. 17C and 17D, the thicknesst1 of the region of the first reflector 200 close to the light sourcemodule 100 may be less than the thickness t2 of the region of the firstreflector 200 distant from the light source module 100.

Additionally, as illustrated in FIG. 17D, the first reflector 200 mayinclude not only an inclined surface, but also a flat surface.

More specifically, the region of the first reflector 200 close to thelight source module 100 may include an inclined surface, and the regionof the first reflector 200 distant from the light source module 100 mayinclude a flat surface.

Here, a length L1 of the inclined surface and a length L2 of the flatsurface may be equal to each other, or may differ from each other, asoccasion demands.

A reflective pattern may be formed on a surface of the first reflector200.

FIGS. 18A to 18D are views illustrating the first reflector having areflective pattern.

FIG. 18A illustrates a saw-toothed reflective pattern 220, each tooth ofwhich may have a flat surface. FIGS. 18B and 18C illustrate asaw-toothed reflective pattern 220, each tooth of which may have acurved surface.

Here, the reflective pattern 220 illustrated in FIG. 18B has saw teethof a concavely curved surface, whereas the reflective pattern 220illustrated in FIG. 18C has saw teeth of a convexly curved surface.

As occasion demands, as illustrated in FIG. 18D, in the case of thesaw-toothed reflective pattern 220, the size of teeth may graduallyincrease with increasing distance from a fixed end of the firstreflector 200.

Providing the reflective pattern 220 on the first reflector 200 mayachieve higher reflectivity and uniform diffusion of light.

Accordingly, various sizes of the reflective pattern 220 may be formedat a corresponding region based on luminance distribution of the entireillumination unit.

FIG. 19 is a sectional view illustrating an illumination unit includingan optical member, and FIG. 20 is a sectional view illustrating theoptical member of FIG. 19.

As illustrated in FIG. 19, an optical member 600 may be spaced apartfrom the second reflector 300 by a predetermined distance.

As such, an air guide may be defined in a space between the secondreflector 300 and the optical member 600.

The optical member 600, as illustrated in FIG. 20, may have a roughenedpattern 620 formed on an upper surface thereof.

The optical member 600 serves to diffuse light emitted from the lightsource module 100. To increase diffusion effects, the roughened pattern620 may be formed on the upper surface of the optical member 600.

More specifically, the optical member 600 may have a multilayer form.The roughened pattern 620 may be an uppermost layer or any one layer ofthe optical member 600.

The roughened pattern 620 may have a stripe shape extending along thelight source module 100.

In this case, the roughened pattern 620 may include ridges formed on thesurface of the optical member 600. The respective ridges may have afirst face and a second face facing each other, and an angle between thefirst face and the second face may be an acute angle or an obtuse angle.

As occasion demands, the optical member 600 may be formed of at leastone sheet. More specifically, the optical member 600 may selectivelyinclude a diffusion sheet, a prism sheet, a luminance-increasing sheet,or the like.

The diffusion sheet functions to diffuse light emitted from a lightsource, the prism sheet functions to guide diffused light to a lightemitting region, and the luminance-increasing sheet functions toincrease luminance.

The second reflector 300 may include at least one of a metal or a metaloxide. For example, the second reflector 300 may be formed of a metal ormetal oxide having high reflectivity, such as aluminum (Al), silver(Ag), gold (Au) or titanium dioxide (TiO2).

The second reflector 300 may be formed of any one of a reflectivecoating film and a reflective coating material layer. The secondreflector 300 may serve to reflect light emitted from the light sourcemodule 100 toward the optical member 600.

A saw-toothed reflective pattern may be formed on a surface of thesecond reflector 300 facing the optical member 600. The reflectivepattern may be flat or may be curved.

The reason for providing the surface of the second reflector 300 withthe reflective pattern is to uniformly diffuse and reflect light emittedfrom the light source module 100.

As such, through provision of the groove and the reflector having apartial inclined surface for an air guide instead of a light guideplate, the aforementioned embodiments may achieve low weight andmanufacturing costs and uniform luminance.

Accordingly, the illumination unit may achieve enhanced reliability andeconomical efficiency and may be suitable for a wide indoor space.

In addition, a backlight unit, a display apparatus, an indicatorapparatus, and an illumination system, which employ the groove, thefirst and second reflectors, and the light source module according tothe aforementioned embodiments, may be realized. For example, anillumination system may include a lamp, and a street lamp.

FIG. 21 is a view illustrating a display module having an illuminationunit according to an embodiment.

As illustrated in FIG. 20, the display module 20 may include a displaypanel 800 and an illumination unit 700.

The display panel 800 may include a color filter substrate 810 and aThin Film Transistor (TFT) substrate 820, which are bonded to face eachother with a uniform cell gap therebetween. A liquid crystal layer (notshown) may be interposed between the two substrates 810 and 820.

An upper polarizer 830 and a lower polarizer 840 may be disposed atupper and lower sides of the display panel 800. More specifically, theupper polarizer 830 may be disposed on an upper surface of the colorfilter substrate 810, and the lower polarizer 840 may be disposedbeneath a lower surface of the TFT substrate 820.

Although not illustrated, a gate and data drive unit may be provided ata lateral surface of the display panel 800 and may generate a drivesignal to drive the panel 800.

FIGS. 22 and 23 are views illustrating a display apparatus according toan embodiment.

Referring to FIG. 22, the display apparatus 1 may include the displaymodule 20, a front cover 30 and a back cover 35 to surround the displaymodule 20, a drive unit 55 provided at the back cover 35, and a driveunit cover 40 to surround the drive unit 55.

The front cover 30 may include a transparent front panel (not shown) totransmit light. The front panel serves to protect the display module 20spaced apart therefrom by a predetermined distance and to transmit lightemitted from the display module 20, allowing an image displayed on thedisplay module 20 to be seen from the outside.

The back cover 35 may be coupled to the front cover 30 to protect thedisplay module 20.

The drive unit 55 may be placed on a surface of the back cover 35.

The drive unit 55 may include a drive controller 55 a, a main board 55 band a power supply board 55 c.

The drive controller 55 a may be a timing controller. The drivecontroller 55 a serves to adjust an operation timing of each driver ICof the display module 20. The main board 55 b may serve to transmitV-sync, H-sync and R, G and B resolution signals to the timingcontroller. The power supply board 55 c supplies power to the displaymodule 20.

The drive unit 55 may be attached to the back cover 35 and may beenclosed by the drive unit cover 40.

The back cover 35 has a plurality of holes, through which the displaymodule 20 may be connected to the drive unit 55. Also, a stand 60 tosupport the display apparatus 1 may be provided.

In an alternative embodiment, as illustrated in FIG. 23, the drivecontroller 55 a of the drive unit 55 may be provided at the back cover35, whereas the main board 55 b and the power supply board 55 c may beprovided in the stand 60.

The drive unit cover 40 may be configured to enclose only the drive unit55 provided at the back cover 35.

Although the present embodiment illustrates the main board 55 b and thepower supply board 55 c as being provided separately, they may beintegrated with each other, and the disclosure is not limited thereto.

In other embodiments, a backlight unit, a display apparatus, anindicator apparatus, and an illumination system, which include thegroove, the first and second reflectors and the light source module asdescribed in the aforementioned embodiments, may be realized. Forexample, the illumination system may include a lamp or a street lamp.

Although embodiments have been described with reference to a number ofillustrative embodiments thereof, it should be understood that numerousother modifications and embodiments can be devised by those skilled inthe art that will fall within the spirit and scope of the principles ofthis disclosure. More particularly, various variations and modificationsare possible in the component parts and/or arrangements of the subjectcombination arrangement within the scope of the disclosure, the drawingsand the appended claims. In addition to variations and modifications inthe component parts and/or arrangements, alternative uses will also beapparent to those skilled in the art.

What is claimed is:
 1. An illumination unit, comprising: first andsecond reflectors; and at least one light source module disposed betweenthe first and second reflectors, wherein the second reflector includes:at least one inclined surface including at least one inflection point;and at least one first flat surface parallel to the first reflector,wherein the at least one light source module is closer to the at leastone first flat surface than the at least one inclined surface.
 2. Theillumination unit according to claim 1, wherein the at least oneinclined surface includes a plurality of inclined surfaces disposed nextto each other about the at least one inflection point.
 3. Theillumination unit according to claim 2, wherein the inclined surfaceshave different radii of curvature.
 4. The illumination unit according toclaim 2, wherein the second reflector comprises: a first region alignedwith the at least one light source module and being the at least onefirst flat surface; a second region being a first inclined surface whichis inclined downward from the first region; and a third region being asecond inclined surface which is inclined upward from the second region,the inclined surfaces including the first and second inclined surface.5. The illumination unit according to claim 4, wherein the first andsecond inclined surfaces are disposed next to each other about the atleast one inflection point.
 6. The illumination unit according to claim4, wherein the second region is disposed between the first region andthe third region, and wherein the third region is disposed next to thesecond region.
 7. The illumination unit according to claim 4, whereinthe first inclined surface is a curved surface having a first radius ofcurvature, and wherein the second inclined surface is a curved surfacehaving a second radius of curvature.
 8. The illumination unit accordingto claim 7, wherein the first radius of curvature is greater than thesecond radius of curvature.
 9. The illumination unit according to claim7, wherein the first radius of curvature and the second radius ofcurvature are equal to each other.
 10. The illumination unit accordingto claim 4, wherein at least one of the first inclined surface or thesecond inclined surface is a convexly curved surface.
 11. Theillumination unit according to claim 4, wherein at least one of thefirst inclined surface or the second inclined surface is a concavelycurved surface.
 12. The illumination unit according to claim 4, whereinthe first inclined surface is a second flat surface having a firstgradient and the second inclined surface is a third flat surface havinga second gradient.
 13. The illumination unit according to claim 12,wherein the first gradient is greater than the second gradient.
 14. Theillumination unit according to claim 4, wherein the first region isprovided with a specular-reflection sheet, and wherein the second regionand third region are provided with at least one of a specular-reflectionsheet or a diffuse-reflection sheet.
 15. The illumination unit accordingto claim 4, wherein the first, second, and third regions have differentsurface roughness values.
 16. The illumination unit according to claim4, wherein the at least one light source module is spaced apart from thefirst reflector by a first distance, wherein the at least one lightsource module is spaced apart from the first region of the secondreflector by a second distance, and wherein the first distance is lessthan the second distance.
 17. The illumination unit according to claim4, wherein the at least one light source module contacts with both thefirst reflector and the first region of the second reflector.
 18. Theillumination unit according to claim 4, wherein the first regionoverlaps with the first reflector, and wherein a width of the firstregion is less than a width of the first reflector.
 19. The illuminationunit according to claim 4, wherein the second reflector furthercomprises a fourth region disposed next to the third region and locatedat a center of the second reflector.
 20. The illumination unit accordingto claim 19, wherein the fourth region has a gentle shape without apointed portion.